XRD Study of the Influence of Heat Treatment on the Microstructure of Sol-Gel Processed ZrO2-Y2O3 Ceramics

1995 ◽  
Vol 398 ◽  
Author(s):  
C. Barrera-Solano ◽  
M. PiÑero ◽  
C. Jiménez-Solís ◽  
L. Gago-Duport
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Profile Function ◽  
Xrd Study ◽  
Different Temperatures ◽  
Hydrolysis Of Metal Alkoxides ◽  
Induced Changes ◽  
Hydrolysis Of ◽  
Controlled Hydrolysis

ABSTRACTYSZ samples containing 5 and 10 mol% of Y203 were prepared by controlled hydrolysis of metal alkoxides. The dried powders were calcined at 800°C and then they were uniaxially pressed and sintered at different temperatures and next heated at 1400°C (∼ 5 MPa) or annealed at 1600°C for 24 h. The quantitative analysis of the experimental X-ray diffraction (XRD) spectra was performed by Whole Pattern Fitting (WPF). A Pseudo-Voigt (Thompson-Cox-Hastings) was used as shape profile function. The respective phase fractions (wt %) were fitted for both solid state solutions using the scale factor. The heat treatment induced changes are discussed.

LUMINESCENT PROPERTIES OF SOL-GEL DEPOSITED Eu:TiO2 THIN FILMS

2001 ◽  
Vol 15 (17n19) ◽  
pp. 769-773 ◽  
Author(s):  
M. GARCIA-ROCHA ◽  
A. CONDE-GALLARDO ◽  
I. HERNANDEZ-CALDERON ◽  
R. PALOMINO-MERINO
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Si Substrates ◽  
Glass Substrates ◽  
Corning Glass ◽  
Different Temperatures ◽  
Hecd Laser

In this work we show the results on tile growth and optical characterization of TiO 2 thin films doped with Eu atoms. Eu:TiO2 films were grown at room temperature with different Eu concentrations by sol-gel on Si Corning glass substrates. A different crystalline structure is developed for the films deposited on Corning glass than those deposited on Si as observed from x-ray diffraction experiments. Room and low temperature photoluminescence (PL) was measured by using two different lines (325 and 442 nm) of a HeCd laser. A strong PL signal associated to the 5 D 0→7 F 2 transition from Eu +3 was observed. A better emission was obtained from those films deposited on Si substrates, Finally, the evolution of the PL signal is studied when the samples are annealed at different temperatures in O 2 atmosphere.

Structural and Vibrational Properties of Ferroelectric Pb1-xSrxTiO3 Thin Films and Powders

2002 ◽  
Vol 748 ◽  
Author(s):  
M. Jain ◽  
A. Savvinov ◽  
P. S. Dobal ◽  
S. B. Majumder ◽  
R. S. Katiyar ◽  
...  
Keyword(s):  
Thin Films ◽  
Soft Mode ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Vibrational Properties ◽  
X Ray Diffraction ◽  
Phase Transition Temperatures ◽  
Induced Changes ◽  
Pst System

ABSTRACTIn this work we present the structural, and vibrational properties of ferroelectric Pb1-xSrxTiO3 (PST). Thin films of PST were prepared by using sol-gel technique for various compositions with x values ranging from 0.0–1.0. Respective compositions were also prepared in ceramic and powder forms using sol-gel and solid-state reaction methods. X-ray diffraction was used for the structural characterization of these materials. Raman spectroscopy was utilized to study the phases and lattice vibrational modes, especially the soft mode in PST compositions. The temperature dependence of the soft mode frequency for different PST compositions revealed that the phase transition temperatures increased with increasing Pb contents in PST system. Ferroelectric properties of the films were correlated with the substitution-induced changes in the material.

scholarly journals Characterization and photocatalytic study of tantalum oxide nanoparticles prepared by the hydrolysis of tantalum oxo-ethoxide Ta8(μ3-O)2(μ-O)8(μ-OEt)6(OEt)14

2014 ◽  
Vol 5 ◽  
pp. 1082-1090 ◽  
Author(s):  
Subia Ambreen ◽  
N D Pandey ◽  
Peter Mayer ◽  
Ashutosh Pandey
Keyword(s):  
Particle Size ◽  
Sol Gel ◽  
Tantalum Oxide ◽  
Organic Dye ◽  
Oxide Nanoparticles ◽  
Tauc Plot ◽  
Particle Size Analyzer ◽  
Bet Method ◽  
Hydrolysis Of ◽  
Controlled Hydrolysis

Ta8(μ3-O)2(μ-O)8(μ-OEt)6(OEt)14 (1) was obtained by the controlled hydrolysis of tantalum ethoxide Ta(OEt)5 in the presence of ammonia. Compound 1 is considered as the intermediate building block in the sol–gel polymerization of Ta(OEt)5. Further hydrolysis of compound 1 yielded nanoparticles of Ta2O5, which were characterized by various techniques such as TGA-DTA-DSC, UV–vis DRS, XRD, SEM, TEM, particle size analyzer (DLS) and the Brunauer–Emmett–Teller (BET) method. The band gap of the particles was calculated by using the Tauc plot. The photocatalytic activity of Ta2O5 nanoparticles was tested by the degradation of the organic dye rhodamine B.

Nanostructured YSZ Thin Film for Application as Electrolyte in an Electrode Supported SOFC

2012 ◽  
Vol 727-728 ◽  
pp. 873-878
Author(s):  
Cibele Melo Halmenschlager ◽  
Matias de Angelis Korb ◽  
Roberto Neagu ◽  
Carlos Pérez Bergmann ◽  
Célia de Fraga Malfatti
Keyword(s):  
Thin Film ◽  
Heat Treatment ◽  
Treatment Process ◽  
Precursor Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Influence ◽  
Different Temperatures ◽  
Spray Pyrolysis Process ◽  
Fast Increase

The development of solid oxide fuel cell with thin film concepts for an electrode supported design based on the yttria-stabilized zirconia has demonstrated favourable results due to its high chemistry stability in oxidization and environment reduction. The spray pyrolysis process was investigated in order to obtain dense thin films of YSZ on different substrates. The precursor solution was obtained by zirconium and yttrium salt dissolutions in a mixture of water and glycerine in several ratios to study the solvent influence. The substrate was initially heated at 600 °C and during the deposition it ranged from 260-350°C, finishing at a fast increase in temperature of 600°C. The heat treatment was carried out in four different temperatures: 700 °C, 750 °C, 800 °C, and 900 °. The precursors were characterized by thermal analysis. The microstructures of the films were studied using scanning electron microscopy and X-ray diffraction. The results obtained showed that the films obtained were crystalline before the heat treatment process and have shown ionic conductivity above 800°C.

Preparation of TiO2 Thin Films and its Superhydrophilic Properties

2009 ◽  
Vol 620-622 ◽  
pp. 695-698
Author(s):  
Jing Ma ◽  
Wen Xiu Liu ◽  
Xiao Guang Qu ◽  
Dan Ni Yu ◽  
Wen Bin Cao
Keyword(s):  
Thin Film ◽  
Tio2 Thin Film ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Soda Lime ◽  
Contact Angles ◽  
Soda Lime Glass ◽  
Water Contact ◽  
Different Temperatures ◽  
Hydrolysis Of

TiO2 thin film was prepared on soda lime glass by hydrolysis of Ti(OC4H9)4 in alcoholic solutions by sol-gel method combined with spin-coating and calcination different temperatures. Prepared samples were characterized by XRD, FESEM, and measurement of contact angles and transmittance. XRD identification reveals that the films are composed of anatase TiO2 when the annealing temperature was set at 450~550 oC. SiO2 layer was coated on the surface of the glass firstly to barrier the diffusing of sodium ions from the substrate. Light-induced superhydrophilicity of the TiO2 thin film has been investigated. To increase the illumination light intensity will decrease the water contact angle. The superhydrophilicity of the TiO2 thin film will disappear more slowly in the dark than that in the field of ultrasound.

Effect of Annealing Temperature of CoCr2O4 on Structural and Vibrational Properties

2019 ◽  
Vol 11 (11) ◽  
pp. 1079-1081 ◽  
Author(s):  
Prachi Joshi ◽  
Pallavi Saxena ◽  
M. D. Varshney ◽  
V. N. Rai ◽  
A. Mishra
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Auto Combustion ◽  
Different Temperatures ◽  
Disorder Effect ◽  
High Calcination Temperature

CoCr2O4 nanoparticles were prepared by low-temperature sol–gel auto combustion method. In this paper, we have investigated the structural behavior of CoCr2O4 nanoparticles annealed at two different temperatures (600 °C and 800 °C). From the X-ray diffraction (XRD) pattern of CoCr2O4, we have found that there is no change in crystalline structure and it was indexed in the cubic spinel structure with space group Fd3m. It was observed that average crystallite size increases with calcination temperature. High calcination temperature reduced the noise level and enhanced the accuracy of calculated parameters. For both the samples of CoCr2O4, we observed Raman scattering modes at around 471, 516, 539, 561, 590, 626 and 688 cm–1. The additional modes in vibrational spectra appear due to the disorder effect.

The Process of Sol-Gel Method Prepared Bi-2212 Superconductors Tapes

2013 ◽  
Vol 275-277 ◽  
pp. 2300-2303
Author(s):  
Gen Zong Song ◽  
Duo Zhang
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Ni Substrate ◽  
Treatment Conditions ◽  
Drying Conditions ◽  
And Control

In this dissertation, Bi-2212 superconducting tapes was prepared by sol-gel method, in addition we mainly studied heat treatment conditions and sintering material drying conditions of the NiO/Ni substrate, and gived a optimization to the process. The heat treatment process of the NiO/Ni substrate had been researched.Based on previous experience, we explored the temperature of heat treatment and improved the process.Afterheattreatment,the samples was analyzed by metallographic microscope and X-ray diffraction,and we analysed these data. It’s concluded that the dense uniform oxide film can be sintered in 800°C with a 3 hours’ heat treatment.We further explored the conditions of the Bi-2212 superconducting materials.During the preparation. We mainly studied the drying temperature and sintering temperature ,because they would affect the gel phase transition and control components. It has a very important effect on high-quality superconducting strip preparation. Experiments results showed that drying the sample at 510 °C in temperature is best. all the samples was analyzed by X-ray diffraction. We summed up the data derived from experiments , it showed that sintering the sample at 850°C,we can obtain the mixed phase of Bi-2201 and Bi-2212.

Structural and Photoluminescent Properties of Li-Doped ZnO Film Prepared by Sol-Gel Technique

2010 ◽  
Vol 663-665 ◽  
pp. 397-400 ◽  
Author(s):  
Peng Fei Cheng ◽  
Sheng Tao Li ◽  
Han Chen Liu ◽  
Li Xun Song ◽  
Bin Gao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
Treatment Temperature ◽  
Zno Films ◽  
Zno Film ◽  
Substitutional Defect ◽  
Different Temperatures ◽  
Abnormal Phenomenon ◽  
Doped Zno ◽  
Li Content

The effect of an impurity as a donor or an acceptor in ZnO film is determined by its distribution in ZnO lattice. In this paper the distribution of Li is investigated by X-ray diffraction (XRD) and photoluminescence (PL). It is found that Li-doped ZnO films own different dependence on heat treatment temperature by contrast with pure ZnO films. For Li-doped ZnO films, although the crystallinity is promoted after heat treatment at 500oC, it is impeded effectively after heat treatment at 600oC. The abnormal phenomenon implies that Li preferential inhabits at Zn-sublattice to form a substitutional defect as an acceptor unless Li content exceeds its solubility in Zn-sublattice. The change of the PL spectra of pure ZnO films after heat treatment at different temperatures reveals that the PL peak at 650nm origins from interstitial defects. Moreover, with the increase of Li content, the intensity of the peak at 650nm decreases firstly and then increases again. This interesting changing trend further reveals that superfluous Li will enter into the octahedral interspaces as donors. As a conclusion it is proposed that it is difficult to obtain high conductive p-ZnO by monodoping of Li.

Preparation and Electrophoretic Deposition of an Yttrium Silicate Precursor Sol

2009 ◽  
Vol 412 ◽  
pp. 267-272 ◽  
Author(s):  
Jana Grosse-Brauckmann ◽  
Günter Borchardt ◽  
Christos Argirusis
Keyword(s):  
Electrophoretic Deposition ◽  
Sol Gel ◽  
Constant Current ◽  
Particle Charge ◽  
Yttrium Silicate ◽  
Micro Cracks ◽  
Sol Gel Process ◽  
Hydrolysis Of ◽  
Controlled Hydrolysis

. In the present work we used the sol-gel process to prepare Y2SiO5 precursor sols suitable for electrophoretic deposition (EPD). The sol synthesis was performed through the controlled hydrolysis of alkoxide solutions of tetraethoxysilane and yttriumoxoisopropoxide. During sol development emphasis was put on characterization of particles size and zeta potential of the formed aggregates. We succeeded in synthesizing a clear sol containing polymeric aggregates with acceptable particle charge. The electrophoretic deposition on glassy carbon or C/C-SiC slabs led to homogenous layers. At low sol concentrations micro cracks in the deposited layers were observed whereas higher concentrations led to thin and dense layers. During constant current EPD a constant voltage was recorded indicating that the deposited layer does not lead to an increase in resistivity in this kind of EPD system.

Elaboration of Low Field and Room Temperature Magnetoresistive Sensor of La0.7Sr0.3MnO3 Nanoparticles Synthesized by Sol-Gel Method

2015 ◽  
Vol 771 ◽  
pp. 121-124 ◽  
Author(s):  
Christian Fredy Naa ◽  
Didier Fasquelle ◽  
Manuel Mascot ◽  
Mitra Djamal
Keyword(s):  
Room Temperature ◽  
Sol Gel ◽  
Magnetic Sensors ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Magnetoresistive Sensor ◽  
Low Field ◽  
Ferromagnetic Nature ◽  
Different Temperatures

Low field and room temperature operation range are two critical requirements for magnetic sensors. In this paper, nanoparticles of La0.7Sr0.3MnO3 (LSMO) were elaborated to fulfill these requirements. La0.7Sr0.3MnO3 nanoparticles were synthesized using sol-gel method. The physical properties of LSMO were examined by X-Ray diffraction and Scanning Electron Microscope. The ferromagnetic nature of LSMO samples was confirmed by magnetization measurements. Nanoparticles were pressed in shape of pellets and sintered at different temperatures of 900°C, 1000°C, 1100°C and 1200°C. Magnetoresistive measurements were taken at room temperature with magnetic field (μH) in range ±110 mT. The experimental results show maximum magnetoresistive ratio and sensitivity of 1.3% and 0.023%/mT respectively for sample sintered at 1000°C. Other sensor characteristics namely hysteresis error, response time and noise measurement were also given.

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